1. Field of the Invention
The invention relates to a microelectromechanical system package and the method for manufacturing the same, and more particularly, to a wafer-level micromechanical system package and the method for manufacturing the same.
2. Description of the Related Art
Referring to FIG. 1, a conventional micromechanical system package 100 includes a substrate 110 and a microelectromechanical system (MEMS) device 120, such as a transducer or a silicon-based microphone disposed on the substrate 110. A cover 130 is disposed on the substrate 110 to cover the MEMS device 120. A peripheral edge of the cover 130 is electrically connected to the substrate 110 by a conductive adhesive, solder, or the like 140.
The cover 130 is produced from an outer cup 132a formed from a conductive layer of material such as copper, stainless steel, aluminum, or an alloy thereof. The cover 130 further includes an inner cup 132b. The inner cup 132b is also produced from a conductive layer. An inner lining 150 is formed on the inner cup 132b. The inner lining 150 is primarily formed by conductive material. The inner lining 150 protects the chip 120 from electromagnetic, such as RF interference. The cover 130 has apertures or acoustic ports 160 so that an acoustic signal can pass through the acoustic ports 160 to reach the MEMS device 120. Besides, each acoustic port 160 may contain an environmental barrier layer 170 to prevent water, particles and/or light from entering the package 100 and damaging the internal components inside. The environmental barrier layer 170 is disposed between the outer cup 132a and inner cup 132b and is formed to a film by the micro porous polymeric material typically.
The above-mentioned package 100 has been disclosed in U.S. Pat. No. 6,781,231 and has the advantage of being able to shield the MEMS device 120 therein from external electromagnetic interference and environmental influences. However, the mass production of such packages 100 is difficult. Moreover, the package 100 has a large profile and therefore its application is quite limited.
Accordingly, there exists a need to provide a method for manufacturing a microelectromechanical system package to solve the above-mentioned problems.